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11.
Some feminist philosophers criticize the idea of human rights because, they allege, it encapsulates male bias; it is therefore misguided, in their view, to extend moral rights to non-human animals. I argue that the feminist criticism is misguided. Ideas are not biased in favour of men simply because they originate with men, nor are ideas themselves biased in favour of men because men have used them prejudicially. As for the position that women should abandon theories of rights and embrace an ethic that emphasizes care: women who made this choice would not so much liberate themselves from the patriarchy as they would conform to its representation of women as emotional, subjective and irrational. There is, then, no good reason to withhold ascribing rights to non-human animals, based on the criticisms of rights made by some feminists.Some of the material in the discussion of the feminist critique of rights originally appeared in my The Case for Animal Rights: A Decade's Passing inA Quarter Century of Value Inquiry: Presidential Addresses of the American Society of Value Inquiry, edited by Richard T. Hull, pp. 451–455. Amsterdam and Atlanta, GA: Rodopi, 1994. These passages are reprinted with the permission of the editor and publisher, whose thoughtful co-operation is gratefully acknowledged.  相似文献   
12.
Potential for carbon sequestration in Canadian forests and agroecosystems   总被引:2,自引:0,他引:2  
The potential for carbon (C) sequestration was examined in selectedCanadian forest settings and prairie agroecosystems under severalmanagement scenarios. A simple C budget model was developed toquantitatively examine C sequestration potential in living biomass of forestecosystems, in associated forest-product C pools, and in displaced fossil-fuelC. A review of previous studies was conducted to examine C sequestrationpotential in prairie agroecosystems. In the forest settings examined, ourwork suggests that substantial C sequestration opportunities can be realizedin the short term through the establishment of protected forest-C reserves.Where stands can be effectively protected from natural disturbance, peaklevels of biomass C storage can exceed that under alternative managementstrategies for 200 years or more. In settings where it is not feasible tomaintain protected forest-C reserves, C sequestration opportunities can berealized through maximum sustained yield management with harvestedbiomass put towards the displacement of fossil fuels. Because there is afinite capacity for C storage in protected forest-C reserves, harvesting forestbiomass and using it to displace the use of fossil fuels, either directlythrough the production of biofuels or indirectly through the production oflong-lived forest products that displace the use of energy-intensive materialssuch as steel or concrete, can provide the greatest opportunity to mitigategreenhouse gas emissions in the long term. In Canadian prairieagroecosystems, modest C sequestration can be realized while enhancingsoil fertility and improving the efficiency of crop production. This can bedone in situations where soil organic C can be enhanced without relianceupon ongoing inputs of nitrogen fertilizer, or where the use of fossil fuelsin agriculture can be reduced. More substantial C offsets can be generatedthrough the production of dedicated energy crops to displace the use offossil fuels. Where afforestation or reconstruction of native prairieecosystems on previously cultivated land is possible, this represents thegreatest opportunity to sequester C on a per unit-area basis. However,these last two strategies involve the removal of land from crop production,and so they are not applicable on as wide a scale as some other Csequestration options which only involve modifications to currentagricultural practices.  相似文献   
13.
EffectofacidprecipitationonleachingofnutritionsandaluminiumfromforestsoilsDaiZhaohua;LiaoBohan;WangZhihaiWangXingjun;LiuYunxi...  相似文献   
14.
Using a case study of the Lake Abitibi Model Forest (LAMF), this study aims to assess the temporal and spatial variability in carbon storage during 1990–2000, and to present a comprehensive estimation of the carbon budget for LAMF's ecosystems. As well, it provided the information needed by local forest managers to develop ecological and carbon-based indicators and monitor the sustainability of forest ecosystems. Temporal and spatial carbon dynamics were simulated at the landscape level using ecosystem model TRIPLEX1.0 and Geographical Information System (GIS). The simulated net primary productivity (NPP) and carbon storage in forest biomass and soil were compared with field data and results from other studies for Canada's boreal forests. The results show that simulated NPP ranged from 3.26 to 3.34 tC ha−1 yr−1 in the 1990s and was consistent with the range measured during the Boreal Ecosystem-Atmosphere Studies (BOREAS) in central Canada. Modeled NPP was also compared with the estimation from remote sensing data. The density of total above-and belowground biomass was 125.3, 111.8, and 106.5 tC ha−1 for black spruce, trembling aspen, and jack pine in the LAMF ecosystem, respectively. The total carbon density of forested land was estimated at 154.4 tC ha−1 with the proportion of 4:6 for total biomass and soil. The analysis of net carbon balance of ecosystem suggested that the LAMF forest ecosystem was acting as a carbon sink with an allowable harvest in the 1990s.  相似文献   
15.
Effects of acid deposition on forests in south China   总被引:1,自引:0,他引:1  
1IntroductionWiththefastgrowingofmodernindustryandsharplyincreasingofenergyconsumptionprimarilycoal,airpolutionandaciddeposit...  相似文献   
16.
In this study a method is suggested to compare the net carbon dioxide (CO2) emission from the construction of concrete- and wood-framed buildings. The method is then applied to two buildings in Sweden and Finland constructed with wood frames, compared with functionally equivalent buildings constructed with concrete frames. Carbon accounting includes: emissions due to fossil fuel use in the production of building materials; the replacement of fossil fuels by biomass residues from logging, wood processing, construction and demolition; carbon stock changes in forests and buildings; and cement process reactions. The results show that wood-framed construction requires less energy, and emits less CO2 to the atmosphere, than concrete-framed construction. The lifecycle emission difference between the wood- and concrete-framed buildings ranges from 30 to 130 kg C per m2 of floor area. Hence, a net reduction of CO2 emission can be obtained by increasing the proportion of wood-based building materials, relative to concrete materials. The benefits would be greatest if the biomass residues resulting from the production of the wood building materials were fully used in energy supply systems. The carbon mitigation efficiency, expressed in terms of biomass used per unit of reduced carbon emission, is considerably better if the wood is used to replace concrete building material than if the wood is used directly as biofuel.  相似文献   
17.
This paper addresses the combined effects of two sources of disturbance on the boreal forest – climate change and the economic relations of industrial forestry. It describes a theoretical blueprint constructed of concepts from the theory of dissipative structures (derived from the discipline of physical chemistry) and world-systems theory (derived from the discipline of sociology) into a proposed integrated theory pivoting on the concept of social vulnerability. The goal is to examine the key concepts of this theory – vulnerability, resilience and adaptive capacity – as elements of the complex systems perspective provided by dissipative structure principles. The focus on social vulnerability provides the means to establish the role of external economic linkages relevant to industrial forestry – the core/periphery relations of the world-system – as they influence the social vulnerability of the boreal forest SESs. These systems are posited as embedded peripheries, following world-system criteria, and as the focal scale of analysis within a larger hierarchically organized dissipative structure. The goal is to suggest and stimulate ideas for further discussion and exploration, motivated by the premise that any successful climate change mitigation efforts depend on having sound theoretical foundations on which to stand.  相似文献   
18.
We studied the Noel KempffMercado Climate Action Project (NKMCAP),Bolivia, to assess whether forestprotection carbon (C) projects cansignificantly benefit local people. Wehypothesized that forest protection canonly securely deliver C if significantstakeholders are meaningfully andtransparently involved, traditional orcustomary rights are recognized and theirloss compensated for, and there are directlinkages between conservation anddevelopment objective. Our researchfocused on 53 members of the communities ofFlorida, Porvenir and Piso Firme and 36secondary stakeholders. In each of thevillages we held half-day meetings withcommunity leaders, complemented bysemi-structured one-hour interviews with 5,10, and 7 families, representing 20%, 10%and 8% of each community. The long-termimpact of the NKMCAP on the localcommunities may well be positive. However,in the short run, certain sections of thelocal communities are financially poorer. Forest protection projects clearly have thepotential to sequester C, protectbiodiversity and simultaneously contributeto sustainable rural development, but ifthey really are to improve rurallivelihoods, they must be designed andimplemented carefully and participatively.  相似文献   
19.
从天然林水文功能出发,阐述了东北地区天然林削减及其与洪涝灾害的关系,提出了东北地区水患治理方略。同时建议建立防汛信息系统,提高暴雨和洪水预报准确率以及防洪保险灾后重建。  相似文献   
20.
本文在对山东省森林资源和木材供需平衡状况进行系统分析的基础上,利用系统动力学方法建立了山东省森林资源与木材供需平衡模型,通过对不同方案的政策仿真和结果分析,试图提出解决山东省木材供需矛盾的最佳途径,为制定林业发展政策提供依据。  相似文献   
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